Natural Resources
Conservation Service

Ecological site R067AY150WY

Sandy (Sy)

Last updated: 9/07/2023
Accessed: 11/21/2024

Home / Esd catalog / MLRA 067A / Ecological site R067AY150WY

USC

Metric

General information

Provisional. A provisional ecological site description has undergone quality control and quality assurance review. It contains a working state and transition model and enough information to identify the ecological site.

Click to explore map

Figure 1. Mapped extent

Areas shown in blue indicate the maximum mapped extent of this ecological site. Other ecological sites likely occur within the highlighted areas. It is also possible for this ecological site to occur outside of highlighted areas if detailed soil survey has not been completed or recently updated.

MLRA notes

Major Land Resource Area (MLRA): 067A–Central High Plains, Northern Part

MLRA 67A-Central High Plains, Northern Part is located in southeastern Wyoming (58 percent), the southwestern portion of the Nebraska panhandle (38 percent), and extreme northeastern Colorado (4 percent). It is comprised of rolling plains, upland breaks, and river valleys. The major rivers are the North Platte and Laramie. The headwaters of these systems are in the Rocky Mountains. Other tributaries include Crow, Horse, and Lodgepole Creeks. This MLRA is traversed by Interstate 25 and Interstate 80, and by U.S. Highways 26, 30 and 85. Major land uses include rangeland (71 percent), cropland (21 percent), pasture and hayland (1 percent), urban (3 percent), and miscellaneous (4 percent). Cities in this area include Cheyenne, Torrington, and Wheatland, WY; and Kimball, Oshkosh, and Scottsbluff, NE. Land ownership is mostly private. Areas of interest include Scotts Bluff National Monument, Chimney Rock and Fort Laramie National Historic Sites; Hawk Springs, Lake Minatare, and Wildcat Hills State Recreation Areas; Ash Hollow and Guernsey State Parks.

The elevations in MLRA 67A range from approximately 3,300 to 6,200 feet. The average annual precipitation in this area ranges from 13 to17 inches per year, but may increase up to 18 inches per year, in localized areas. Precipitation occurs mostly during the growing season from rapidly developing thunderstorms. Mean annual air temperature ranges from 47 degrees Fahrenheit in the western part to 52 degrees Fahrenheit in the eastern part. Summer temperatures may exceed 100 degrees Fahrenheit. Winter temperatures may drop to sub-zero, and snowfall varies from 20 to 50 inches per year.

Classification relationships

MLRA 67A is in the Western Great Plains Range and Irrigation Land Resource Region. It is in the High Plains Section, of the Great Plains Province, of the Interior Plains (USDA, 2006). MLRA’s can be defined by climate, landscapes, geology, and annual precipitation zones (PZ). Other features such as landforms, soil properties, and key vegetation further refine these concepts, and are described at the Ecological Site Description (ESD) level.

Relationship to Other Classifications:

Natural Resource Conservation Service (NRCS) Classification Hierarchy (from highest to lowest unit):
Physiographic Division, Physiographic Province, Physiographic Section, Land Resource Region, Major Land Resource Area, Land Resource Unit
(Fenneman, 1946)

United States Forest Service (USFS) Classification Hierarchy (from highest to lowest unit):
Domain, Division, Province, Section, Subsection, Landtype Association, Landtype, Landtype Phase
(Cleland et al, 1997)

Revision Notes:

The Sandy 12-17 inch PZ site was developed by an earlier version of the Sandy (Sy) 12-17 inch Precipitation Zone ESD (2005, updated 2008). The earlier version of the Sandy 12-17 inch PZ ESD were based on input from NRCS (formerly Soil Conservation Service) and historical information obtained from the Sandy 12-14 Southern Plains (SP) and Sandy 15-17 SP Range Site Descriptions (1988). This ESD meets the Provisional requirements of the National Ecological Site Handbook (NESH). This ESD will continue refinement towards an Approved status according to the NESH.

Ecological site concept

The Sandy site is a run-off site on slopes of less than six percent. The soil is deeper than 20 inches to bedrock, is not alkaline or saline, and does not have a high volume of coarse fragments on the surface. The surface and subsurface textures have a high degree of sand in the profile.

Associated sites

R067AY162WY	Shallow (Sw) This ecological site is commonly adjacent.

R067AY162WY

Shallow (Sw)

This ecological site is commonly adjacent.

Similar sites

R067AY122WY	Loamy (Ly) The Loamy Ecological Site has loamy textures in the surface and subsurface soil profile.
R067AY152WY	Sandy Lowland (SyL) The Sandy Lowland Ecological Site is a run-on site.
R067AY162WY	Shallow (Sw) The Shallow Ecological Site has a root-restrictive layer within 20 inches of the soil surface.
R067AY104WY	Clayey (Cy) The Clayey Ecological Site has clayey textures in the soil surface and subsurface profile.

Table 1. Dominant plant species

Tree	Not specified
Shrub	(1) Artemisia filifolia (2) Artemisia cana
Herbaceous	(1) Hesperostipa comata (2) Calamovilfa longifolia

Download full description

Physiographic features

This site occurs on nearly level to slightly sloping toeslopes, footslopes, or backslopes of hills on the uplands or dissected plains. It also occurs on slightly sloping fans or on level terraces of the uplands or dissected plains.

Table 2. Representative physiographic features

Landforms	(1) Hill (2) Fan (3) Terrace
Runoff class	Very low to medium
Flooding frequency	None
Ponding frequency	None
Elevation	914 – 1,981 m
Slope	0 – 9%
Water table depth	203 – 508 cm
Aspect	Aspect is not a significant factor

Climatic features

Wide fluctuations in precipitation may occur from year to year, as well as occasional periods of drought (longer than one year in duration). Two-thirds of the annual precipitation occurs during the growing season from April to September. The mean annual air temperature (MAAT) ranges from 47 degrees Fahrenheit in the western part to 52 degrees Fahrenheit in the eastern part. Cold air outbreaks from Canada in winter move rapidly from northwest to southeast and account for extreme minimum temperatures. Chinook winds may also occur in winter and bring rapid rises in temperature. Extreme storms may occur during the winter, but most severely affect ranch operations during the late winter and spring months. High-intensity afternoon thunderstorms may arise in summer. Wind speed averages about 8 miles per hour, ranging from 10 during the spring to 7 during late summer. Daytime winds are generally stronger than nighttime and occasional strong storms may bring brief periods of high winds with gusts to more than 75 mph. The average length of the freeze-free period (28 degrees Fahrenheit) is 150 days from May 4 to October 1. The average frost-free period (32 degrees Fahrenheit) is 128 days from May 16 to September 21. Growing season increases from west to east (Wyoming to Nebraska). Growth of native cool-season plants begins about April 1 and continues to mid-June. Native warm-season plants begin growth about May 15 and continue to about August 15. Regrowth of cool-season plants occur in September in most years, depending upon moisture.

Table 3. Representative climatic features

Frost-free period (characteristic range)	85-117 days
Freeze-free period (characteristic range)	119-135 days
Precipitation total (characteristic range)	406-432 mm
Frost-free period (average)	103 days
Freeze-free period (average)	128 days
Precipitation total (average)	406 mm

Characteristic range

Actual range

Bar

Line

Figure 2. Monthly precipitation range

Characteristic range

Actual range

Bar

Line

Figure 3. Monthly minimum temperature range

Characteristic range

Actual range

Bar

Line

Figure 4. Monthly maximum temperature range

Bar

Line

Figure 5. Monthly average minimum and maximum temperature

Figure 6. Annual precipitation pattern

Figure 7. Annual average temperature pattern

Climate stations used

(1) KIMBALL 2NE [USC00254440], Kimball, NE
(2) CHEYENNE [USW00024018], Cheyenne, WY
(3) SCOTTSBLUFF HEILIG AP [USW00024028], Scottsbluff, NE
(4) BRIDGEPORT [USC00251145], Bridgeport, NE
(5) HARRISBURG 12WNW [USC00253605], Harrisburg, NE
(6) CHUGWATER [USC00481730], Chugwater, WY
(7) OLD FT LARAMIE [USC00486852], Yoder, WY
(8) PHILLIPS [USC00487200], LaGrange, WY
(9) WHEATLAND 4 N [USC00489615], Wheatland, WY
(10) OSHKOSH [USC00256385], Oshkosh, NE

Soil features

The soils on this site are typically deep to very deep, but includes moderately deep, well drained soils that formed from eolian deposits or alluvium; moderately deep soils formed from residuum derived from sandstone. They typically in the moderate to moderately rapid permeability class. The available water capacity is low to moderate. Available water is the portion of water in a soil that can be readily absorbed by plant roots. The soil moisture regime is typically aridic ustic. The soil temperature regime is mesic.

The surface layer of the soils in this site are typically fine sandy loam, loamy very fine sand, or very fine sandy loam, but may include sandy loam and loamy fine sand. The surface layer ranges from a depth of 5 to 12 inches thick. The subsoil is typically fine sandy loam, sandy loam, or loamy very fine sand, but may include very fine sandy loam. The subsoil typically contains less than 5 percent rock fragments, but this may range up to 35 percent in some soils. Soils in this site are typically leached of carbonates 8 to 30 inches or more; some soils may have carbonates at the surface. These soils are susceptible to erosion by wind if not covered. The potential for water erosion accelerates with increasing slope.

Surface soil structure is fine to medium granular, and the structure below the surface is subangular blocky and/or prismatic. Soil structure describes the manner in which soil particles are aggregated and defines the nature of the system of pores and channels in a soil.

Major soil series correlated to this ecological site include: Aberone, Albinas, Alice, Anselmo, Ascalon, Ashollow, Bayard, Blanche, Bordeaux, Bresser, Busher, Chappell, Curabith, Jayem, Julesburg, Keeline, Mainter, Manter, Otero, Paoli, Phiferson, Sarben, Sidney, Turnercrest, Vetal, and Vonalee.

Other soil series that have been correlated to this site include: Chugcity, Claprych, Graystone, Greenhope, Hawksprings, and Sweatbee.

The attributes listed below represent 0-40 inches in depth or to the first restrictive layer.

Note: Revisions to soil surveys are on-going. For the most recent updates, visit the Web Soil Survey, the official site for soils information: http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx.

Figure 8. Vonalee sandy loam, Laramie County, WY (Western Part)

Table 4. Representative soil features

Parent material	(1) Alluvium (2) Eolian deposits
Surface texture	(1) Fine sandy loam (2) Very fine sandy loam (3) Loamy very fine sand
Drainage class	Well drained
Permeability class	Moderate to moderately rapid
Soil depth	51 – 203 cm
Surface fragment cover <=3"	0 – 5%
Surface fragment cover >3"	0%
Available water capacity (0-101.6cm)	11.18 – 19.3 cm
Calcium carbonate equivalent (0-101.6cm)	0 – 10%
Electrical conductivity (0-101.6cm)	0 – 2 mmhos/cm
Sodium adsorption ratio (0-101.6cm)	0 – 5
Soil reaction (1:1 water) (0-101.6cm)	6.6 – 8.4
Subsurface fragment volume <=3" (0-101.6cm)	0 – 35%
Subsurface fragment volume >3" (0-101.6cm)	0%

Ecological dynamics

The information in this ESD, including the state-and-transition model (STM) diagram, was developed using archeological and historical data, professional experience, and scientific studies. The information is representative of a dynamic set of plant communities that represent the complex interaction of several ecological processes. The plant composition has been determined by study of rangeland relic areas, areas protected from excessive disturbance, seasonal use pastures, short duration/time controlled grazing strategies, and historical accounts.

The Sandy ecological site is characterized by four states: Reference, Sod-bound, Increased Bare Ground, and Tilled. The Reference State is characterized by cool-season mid bunchgrasses (needle and thread), warm-season mid rhizomatous grasses (prairie sandreed), and warm-season mid bunchgrass (little bluestem). Secondary grasses are warm-season tall bunchgrass (sand bluestem), and warm-season shortgrass (blue grama). Other grasses and grass-likes include western wheatgrass, Indian ricegrass, prairie Junegrass, sand dropseed, and threadleaf sedge. A minor component of forbs and shrubs are also present. The Sod-bound State is characterized by warm-season shortgrass (blue grama) and grasslikes (threadleaf sedge). The Increased Bare Ground State is characterized by annual grasses (sixweeks fescue), forbs (spreading buckwheat and annuals), and shrubs (broom snakeweed, and pricklypear). Invasives include cheatgrass.

As this site begins to deteriorate from a combination of frequent and severe grazing during the growing season, bunchgrasses such as needle and thread and green needlegrass decrease in both frequency and production. Grasses such as blue grama and threadleaf sedge increase. Under continued frequent and severe defoliation with no rest periods, rhizomatous wheatgrasses also begins to decrease. Forbs and shrubs such as curlycup gumweed, Cuman ragweed, hairy false goldenaster, spreading buckwheat, pricklypear, and broom snakeweed also increase. If continued, the plant community becomes sod-bound, and all mid-grasses can eventually be removed from the plant community. Over the long-term, this continuous use in combination with high stock densities results in a broken sod, with areas of bare ground developing, and species such as broom snakeweed and annual bromes (cheatgrass), invading.

The degree of grazing has a significant impact on the ecological dynamics of the site. This region was historically occupied by large grazing animals, such as bison, elk, pronghorn, and mule deer. Grazing by these large herbivores, along with climatic and seasonal weather fluctuations, had a major influence on the ecological dynamics of the site. Deer and pronghorn are widely distributed throughout the MLRA. Secondary influences of herbivory by species such as prairie dogs and other small rodents, insects, and root-feeding organisms continues to impact the vegetation.

Historically, grazing patterns by herds of large ungulates were driven by water distribution, precipitation events, drought events, and fire. It is believed that grazing periods would have been shorter, followed by longer recovery periods. These large migrating herds impacted the ecological processes of nutrient and hydrologic cycles, by urination, trampling (incorporation of litter into the soil surface), and breaking of surface crust, (which increases water infiltration).

Today, livestock grazing, especially beef cattle has been a major influence on the ecological dynamics of the site. Grazing management, coupled with the effects of annual climatic variations, largely dictates the plant communities for the site.

Recurrent drought has historically impacted the vegetation of this region. Changes in species composition vary depending upon the duration and severity of the drought cycle and prior grazing management. Drought events since 2002 have significantly increased mortality of blue grama and buffalograss in some locales.

This site developed with occasional fire as part of the ecological processes. Historic fire frequency (pre-industrial) is estimated at 10 to14 years (Guyette, 2012), randomly distributed, and started by lightning at various times throughout the growing season. Early human inhabitants also were likely to start fires for various reasons (deliberate or accidental). It is believed that fires were set as a management tool for attracting herds of large migratory herbivores (Stewart, 2002). The impact of fire over the past 100 years has been relatively insignificant due to the human control of wildfires and the lack of acceptance of prescribed fire as a management tool.

State and transition model

More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective text

Ecosystem states

1. Reference State

2. Sod-bound State

3. Increased Bare Ground State

4. Tilled State

T1A	-	Excessive grazing. Lack of fire.
T1B	-	Excessive grazing. Lack of fire.
T1C	-	Mechanical tillage.
T2A	-	Excessive grazing. Lack of fire.

State 1 submodel, plant communities

1.1. Hesperostipa comata-Calamovilfa longifolia (needle and thread-prairie sandreed).

1.2. Hesperostipa comata-Bouteloua gracilis (needle and thread-blue grama).

1.3. Hesperostipa comata-Calamovilfa longifolia (needle and thread-prairie sandreed) Low Plant Density Community.

1.1A	-	Excessive grazing. Lack of fire.
1.1B	-	Non-use. Lack of fire.
1.2A	-	Prescribed grazing. Prescribed fire.
1.3A	-	Prescribed grazing. Prescribed fire.

State 1
Reference State

The Reference State is characterized by three distinct plant community phases. The plant communities, and various successional stages between them, represent the natural range of variability within the Reference State.

Dominant plant species

sand sagebrush (Artemisia filifolia), shrub
silver sagebrush (Artemisia cana), shrub
needle and thread (Hesperostipa comata), grass
prairie sandreed (Calamovilfa longifolia), grass

Community 1.1
Hesperostipa comata-Calamovilfa longifolia (needle and thread-prairie sandreed).

Figure 9. Sandy 12-17" PZ, Cheyenne County, NE

The Reference Plant Community is the interpretive plant community for this site. This community developed with grazing by large herbivores and is suited to grazing by domestic livestock. Historically, fires likely occurred infrequently, and were randomly distributed. This plant community can be found on areas where grazed plants receive adequate periods of recovery during the growing season. The potential vegetation is about 70 to 95 percent grasses and grass-likes, 5 to15 percent forbs, and 0 to15 percent woody plants. In the western portion of the MLRA, the plant community consists predominantly cool-season mid-grasses, with a significant component of warm-season mid-grasses. In the eastern portion of the MLRA, the plant community is predominantly warm-season with a significant cool-season component. This plant community is predominantly needle and thread, prairie sandreed, and little bluestem. Secondary grasses are sand bluestem, Indian ricegrass, blue grama, and western wheatgrass. Minor grasses and grasslikes that may occur include streambank (thickspike) wheatgrass, sideoats grama, prairie Junegrass, and sand dropseed. A variety of forbs such as scarlet globemallow, lemon scurfpea, prairie spiderwort, and purple prairie clover; half-shrubs such as silver- and sand sagebrush; and shrubs such as western sandcherry also occur. Plant diversity is high. In the 12 to 14 inch Precipitation Zone (PZ), the total annual production (air-dry weight) is about 1,300 pounds per acre during an average year, but ranges from about 750 pounds per acre in unfavorable years to about 1,750 pounds per acre in above-average years. In the 15 to 1 inch PZ, the total annual production (air-dry weight) is about 1,500 pounds per acre during an average year, but ranges from about 1,000 pounds per acre in unfavorable years to about 2,000 pounds per acre in above-average years. Community dynamics (nutrient and water cycles, and energy flow) are functioning properly. Infiltration rates are moderate, and soil erosion is low. Litter is properly distributed where vegetative cover is continuous. Decadence and natural plant mortality are low. This community is resistant to many disturbances except heavy, continuous grazing, tillage, or development into urban or other uses.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
needle and thread (Hesperostipa comata), grass
prairie sandreed (Calamovilfa longifolia), grass

Figure 10. Annual production by plant type (representative values) or group (midpoint values)

Figure 11. Plant community growth curve (percent production by month). WY1104, 12-14SP upland sites w/ warm. 12-14" Precipitation Zone, Southern Plains (SP) with warm-season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	20	35	30	5	5	0	0	0

Community 1.2
Hesperostipa comata-Bouteloua gracilis (needle and thread-blue grama).

The plant community has a reduced component of mid-grasses with an under-story of short sod-forming grasses. Dominant grasses include needle and thread, blue grama, and prairie sandreed. A cool-season/warm-season shift may occur depending upon the predominant season of use. Recurrent heavy, continuous grazing in the spring eventually reduces the cool-season grasses such as needle and thread and the rhizomatous wheatgrasses. Likewise, recurrent heavy, continuous grazing in the summer reduces the warm-season bunchgrasses such as little bluestem and sand bluestem. Prairie sandreed is present and distributed across the site is somewhat reduced amounts. The significant forbs include dotted gayfeather, white sagebrush, spiderworts, and upright prairie coneflower. Shrubs in this community include sand sagebrush, silver sagebrush, Arkansas rose, fringed sagewort, and broom snakeweed. Compared to the Reference Plant Community, blue grama and threadleaf sedge have increased. All of the mid-grass species are present but in lesser amounts, especially the bunchgrasses. Plant diversity is moderate. In the 12 to 14 inch PZ, the total annual production (air-dry weight) is about 900 pounds per acre during an average year, but ranges from about 600 pounds per acre in unfavorable years to about 1,200 pounds per acre in above average years. In the 15 to 17 inch PZ, the total annual production (air-dry weight) is about 1,100 pounds per acre during an average year, but ranges from about 750 pounds per acre in unfavorable years to about 1,450 pounds per acre in above average years. Total aboveground biomass has been reduced. Reduction of rhizomatous wheatgrasses, nitrogen-fixing forbs, and increased warm-season shortgrasses have begun to alter the biotic integrity of this community. Water and nutrient cycles may be impaired. Nearly all plant species typically found in the Reference Plant Community are present and respond to changes in grazing management.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
needle and thread (Hesperostipa comata), grass
blue grama (Bouteloua gracilis), grass

Figure 12. Plant community growth curve (percent production by month). WY1104, 12-14SP upland sites w/ warm. 12-14" Precipitation Zone, Southern Plains (SP) with warm-season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	20	35	30	5	5	0	0	0

Community 1.3
Hesperostipa comata-Calamovilfa longifolia (needle and thread-prairie sandreed) Low Plant Density Community.

This plant community developed under many years of non-use and lack of fire. Plant species resemble the Reference Plant Community however, frequency and production are reduced. Eventually, litter levels can become high enough to cause decadence and mortality of the stand. Bunchgrasses typically develop dead centers and rhizomatous grasses can form small decadent communities due to a lack of impact by grazing animals. Much of the available nutrients are tied up in standing dead plant material and increased amounts of litter. The semiarid environment and the absence of animal traffic to break down litter slows nutrient recycling. Cool-season grasses, and pricklypear have typically increased. Blue grama is reduced. Dominant grasses include prairie sandreed, needle and thread, and western wheatgrass. Other species include sand dropseed and threadleaf sedge. Dominant forbs include annual sunflower and tenpetal blazingstar (also known as Mentzelia). Dominant shrubs include sand sagebrush, silver sagebrush, pricklypear and prairie (fringed) sagewort. Invasive grasses such as cheatgrass tend to encroach under these conditions. Water flow patterns and pedestalling can become apparent. Infiltration is reduced and runoff is increased. In advanced stages of non-use or lack of fire, bare areas increase, causing an erosion concern. In the 12 to 1 inch PZ, the total annual production (air-dry weight) is about 1,000 pounds per acre during an average year, but ranges from about 650 pounds per acre in unfavorable years to about 1,350 pounds per acre in above-average years. In the 15 to 17 inch PZ, the total annual production (air-dry weight) is about 1,500 pounds per acre during an average year, but ranges from about 1,000 pounds per acre in unfavorable years to about 2,000 pounds per acre in above-average years.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
needle and thread (Hesperostipa comata), grass
prairie sandreed (Calamovilfa longifolia), grass

Figure 13. Plant community growth curve (percent production by month). WY1101, 12-14SP Upland sites w/o warm seasons. 12-14" Precipitation Zone, Southern Plains (SP) without warm season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	25	40	15	5	10	0	0	0

Pathway 1.1A
Community 1.1 to 1.2

Long-term, heavy, continuous grazing without adequate recovery between grazing events and lack of fire shifts this plant community toward the 1.2 Community. Drought accelerates this process. Biotic integrity, and water and nutrient cycles may become impaired as a result of this community pathway.

Pathway 1.1B
Community 1.1 to 1.3

Non-use and lack of fire cause the Reference Plant Community to shift toward the 1.3 Community. Plant decadence and standing dead plant material impede energy flow. Initially, excess litter increases. Eventually, native plant density begins to decrease and annuals and introduced species may begin to invade. Water and nutrient cycles are impaired as a result of this community pathway.

Pathway 1.2A
Community 1.2 to 1.1

Grazing that allows for adequate recovery between grazing events, proper stocking rates, and prescribed fire shift this Community back to the Reference Plant Community.

Conservation practices

Prescribed Burning
Prescribed Grazing

Pathway 1.3A
Community 1.3 to 1.1

The return of grazing with adequate recovery and normal fire frequency shifts this plant community toward the Reference Plant Community. This change can occur in a relatively short time frame with the return of these disturbances.

Conservation practices

Prescribed Burning
Prescribed Grazing

State 2
Sod-bound State

An ecological threshold has been crossed and a significant amount of production and diversity has been lost when compared to the Reference State. Significant biotic and soil changes have negatively impacted energy flow and nutrient and hydrologic cycles. This is a very stable state, resistant to change due to the high tolerance of blue grama and threadleaf sedge to grazing, the development of a shallow root system (aka root pan), and subsequent changes in hydrology and nutrient cycling. The loss of other functional/structural groups such as cool-season bunch and rhizomatous grasses, forbs, and shrubs, reduces the biodiversity productivity of this site.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
blue grama (Bouteloua gracilis), grass
threadleaf sedge (Carex filifolia), grass

Community 2.1
Bouteloua gracilis-Carex filifolia (blue grama-threadleaf sedge).

Initially, this plant community is dominated by sod-forming grasses and grasslikes, such as blue grama and threadleaf sedge, with remnants of mid-grasses such as prairie sandreed, sand dropseed, and some rhizomatous wheatgrass. Forbs include Cuman ragweed (western ragweed), lemon scurfpea, hairy false goldenaster, white sagebrush, and skeletonplant. Shrubs such as spreading buckwheat, broom snakeweed, fringed sagewort, and pricklypear continue to increase. Under long-term frequent and severe defoliation, blue grama and threadleaf sedge have become sod-bound in localized colonies and exhibit a mosaic appearance. Other minor grasses are sand dropseed, Fendler threeawn, and annuals. The mid-grasses and palatable forbs have been eliminated. Plant diversity is very low. Energy flow and water and mineral cycles have been negatively affected. Litter levels are very low and unevenly distributed. In the 12 to 14 inch PZ, the total annual production (air-dry weight) is about 500 pounds per acre during an average year, but ranges from about 350 pounds per acre in unfavorable years to about 650 pounds per acre in above-average years. In the 15 to 17 inch PZ, the total annual production (air-dry weight) is about 600 pounds per acre during an average year, but ranges from about 400 pounds per acre in unfavorable years to about 800 pounds per acre in above-average years. This plant community is extremely resistant to change. Many plant species are missing and a seed source is not readily available. Also, sod-forming grasses tend to maintain themselves due to their resistance to any further overgrazing.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
blue grama (Bouteloua gracilis), grass
threadleaf sedge (Carex filifolia), grass

Figure 14. Plant community growth curve (percent production by month). WY1104, 12-14SP upland sites w/ warm. 12-14" Precipitation Zone, Southern Plains (SP) with warm-season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	20	35	30	5	5	0	0	0

State 3
Increased Bare Ground State

The hazard of soil erosion has increased due to the increase of bare ground. Runoff is typically high and infiltration is low. All ecological functions are impaired. An ecological threshold has been crossed. The loss of organic matter and carbon reserves are resource concerns.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
Fendler threeawn (Aristida purpurea var. longiseta), grass
threadleaf sedge (Carex filifolia), grass
burningbush (Bassia scoparia), other herbaceous
Russian thistle (Salsola), other herbaceous

Community 3.1
Bassia scoparia-Salsola/Aristida purpurea-Carex filifolia (burningbush-Russian thistle/Fendler threeawn-threadleaf sedge).

The plant composition is made of annuals with a few species of perennial forbs and grasses that are very tolerant to frequent and severe defoliation. The dominant grasses include blue grama, threadleaf sedge, and Fendler threeawn. Annual grasses and forbs such as cheatgrass, sixweeks fescue, Russian thistle, and burningbush have increased or invaded. The dominant forbs include curlycup gumweed, Cuman (western) ragweed, and hairy false goldenaster. Broom snakeweed, spreading buckwheat, and pricklypear are increasing. In the 12 to 14 inch PZ, the total annual production (air-dry weight) is about 500 pounds per acre during an average year, but ranges from about 350 pounds per acre in unfavorable years to about 650 pounds per acre in above-average years. In the 15 to 17 inch PZ, the total annual production (air-dry weight) is about 600 pounds per acre during an average year, but ranges from about 400 pounds per acre in unfavorable years to about 800 pounds per acre in above-average years.

Dominant plant species

silver sagebrush (Artemisia cana), shrub
sand sagebrush (Artemisia filifolia), shrub
Fendler threeawn (Aristida purpurea var. longiseta), grass
threadleaf sedge (Carex filifolia), grass
burningbush (Bassia scoparia), other herbaceous
Russian thistle (Salsola), other herbaceous

Figure 15. Plant community growth curve (percent production by month). WY1104, 12-14SP upland sites w/ warm. 12-14" Precipitation Zone, Southern Plains (SP) with warm-season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	20	35	30	5	5	0	0	0

State 4
Tilled State

The Tilled State is the result of the site mechanical farming operations. An ecological threshold has been crossed due to complete removal of vegetation and of soil tillage. Physical, chemical, and biological soil properties have been dramatically altered. There is no restorative pathway known at this time.

Dominant plant species

sixweeks fescue (Vulpia octoflora), grass
cheatgrass (Bromus tectorum), grass
burningbush (Bassia scoparia), other herbaceous
Russian thistle (Salsola), other herbaceous

Community 4.1
Bassia scoparia-Salsola/Vulpia octoflora-Bromus tectorum (burningbush-Russian thistle/six weeks fescue-cheatgrass).

Go-back land is created when the soil is tilled or farmed (sodbusted) and abandoned. All of the native plants are eliminated, soil organic matter is reduced, soil structure is degraded, and a plowpan or compacted layer is formed. Residual synthetic chemicals often remain from past farming operations, and erosion processes may be active. Go-back land evolves through several plant communities beginning with an early annual plant community, which initiates the revegetation process. Plants such as Russian thistle, burningbush, sixweeks fescue, cheatgrass, and other annuals begin to establish. These plants give some protection from erosion and start to build minor levels of soil organic matter. Threeawn, sand dropseed, and several other early perennials can dominate the plant community for five to eight years or more. Eventually western wheatgrass, little bluestem, needle and thread, and other natives become re-established. Blue grama and threadleaf sedge are absent. Forbs can include annual sunflower, tenpetal blazingstar (Mentzelia), and Rocky Mountain beeplant. Where Go-back Land has eroded to parent material, the slow process of soil development and re-establishment of vegetation begins. This is a very slow process (100 years or more). A new eco-site may evolve depending upon the severity of soil and parent material erosion, and parent material.

Dominant plant species

sixweeks fescue (Vulpia octoflora), grass
cheatgrass (Bromus tectorum), grass
burningbush (Bassia scoparia), other herbaceous
Russian thistle (Salsola), other herbaceous

Figure 16. Plant community growth curve (percent production by month). WY1101, 12-14SP Upland sites w/o warm seasons. 12-14" Precipitation Zone, Southern Plains (SP) without warm season (grass) species.

Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
J	F	M	A	M	J	J	A	S	O	N	D
0	0	0	5	25	40	15	5	10	0	0	0

Community 4.2
Seeded Community

This plant community can vary considerably depending upon how eroded the soil was, the species seeded, the stand that was established, how long ago the stand was established, and the management of the stand since establishment. The Sandy Ecological Site has been converted to cropland in some areas.

Transition T1A
State 1 to 2

Long-term, heavy, continuous grazing and lack of fire shift this plant community across an ecological threshold toward the Sod-bound State. Biotic integrity and hydrologic function are impaired as a result of this transition.

Transition T1B
State 1 to 3

Long-term heavy, continuous, grazing and lack of fire shift this plant community across an ecological threshold toward the Increased Bare Ground State. Erosion and loss of organic matter and carbon reserves are concerns. Non-native exotic plants are likely to invade.

Transition T1C
State 1 to 4

Mechanical tillage of this ecological site causes an immediate transition across an ecological threshold to the Tilled State. This transition can occur from any plant community and is irreversible.

Transition T2A
State 2 to 3

Long-term heavy, continuous, grazing and lack of fire cause a shift across an ecological threshold to the Increase Bare Ground State. Erosion and loss of organic matter are resource concerns. Annual plants such as sixweeks fescue, and cheatgrass are likely to increase or invade as a result of this transition.

Additional community tables

Table 5. Community 1.1 plant community composition

Group	Common name	Symbol	Scientific name	Annual production (kg/hectare)	Foliar cover (%)
Grass/Grasslike
1	12"-14"			219–729
	prairie sandreed	CALO	Calamovilfa longifolia	146–437	–
	little bluestem	SCSC	Schizachyrium scoparium	73–291	–
	sand bluestem	ANHA	Andropogon hallii	0–219	–
2	12"-14"			219–583
	needle and thread	HECO26	Hesperostipa comata	219–583	–
	Indian ricegrass	ACHY	Achnatherum hymenoides	0–146	–
3	12"-14"			73–219
	blue grama	BOGR2	Bouteloua gracilis	73–219	–
4	12-14"			73–146
	thickspike wheatgrass	ELLA3	Elymus lanceolatus	0–146	–
	western wheatgrass	PASM	Pascopyrum smithii	73–146	–
5	12"-14"			73–146
	Grass, perennial	2GP	Grass, perennial	0–73	–
	sideoats grama	BOCU	Bouteloua curtipendula	0–73	–
	prairie Junegrass	KOMA	Koeleria macrantha	0–73	–
	sand dropseed	SPCR	Sporobolus cryptandrus	0–73	–
	threeawn	ARIST	Aristida	0–29	–
6	12"-14"			0–146
	threadleaf sedge	CAFI	Carex filifolia	0–146	–
	sedge	CAREX	Carex	0–73	–
9	15"-17"			252–841
	prairie sandreed	CALO	Calamovilfa longifolia	168–504	–
	little bluestem	SCSC	Schizachyrium scoparium	84–336	–
	sand bluestem	ANHA	Andropogon hallii	0–252	–
10	15"-17"			252–673
	needle and thread	HECO26	Hesperostipa comata	252–673	–
	Indian ricegrass	ACHY	Achnatherum hymenoides	0–168	–
11	15"-17"			84–252
	blue grama	BOGR2	Bouteloua gracilis	84–252	–
12	15"-17"			84–168
	thickspike wheatgrass	ELLA3	Elymus lanceolatus	0–168	–
	western wheatgrass	PASM	Pascopyrum smithii	84–168	–
13	15"-17"			84–168
	sand dropseed	SPCR	Sporobolus cryptandrus	0–84	–
	Grass, perennial	2GP	Grass, perennial	0–84	–
	sideoats grama	BOCU	Bouteloua curtipendula	0–84	–
	prairie Junegrass	KOMA	Koeleria macrantha	0–84	–
	threeawn	ARIST	Aristida	0–34	–
14	15"-17"			0–168
	threadleaf sedge	CAFI	Carex filifolia	0–168	–
	sedge	CAREX	Carex	0–84	–
Forb
7	12"-14"			73–219
	Forb, perennial	2FP	Forb, perennial	0–73	–
	Cuman ragweed	AMPS	Ambrosia psilostachya	0–29	–
	pussytoes	ANTEN	Antennaria	0–29	–
	white sagebrush	ARLU	Artemisia ludoviciana	0–29	–
	milkvetch	ASTRA	Astragalus	0–29	–
	false boneset	BREU	Brickellia eupatorioides	0–29	–
	prairie clover	DALEA	Dalea	0–29	–
	larkspur	DELPH	Delphinium	0–29	–
	sanddune wallflower	ERCA14	Erysimum capitatum	0–29	–
	scarlet beeblossom	GACO5	Gaura coccinea	0–29	–
	hairy false goldenaster	HEVI4	Heterotheca villosa	0–29	–
	bush morning-glory	IPLE	Ipomoea leptophylla	0–29	–
	dotted blazing star	LIPU	Liatris punctata	0–29	–
	rush skeletonplant	LYJU	Lygodesmia juncea	0–29	–
	bractless blazingstar	MENU	Mentzelia nuda	0–29	–
	evening primrose	OENOT	Oenothera	0–29	–
	pincushion cactus	PEDIO	Pediocactus	0–29	–
	beardtongue	PENST	Penstemon	0–29	–
	sleeping popcornflower	PLSCH	Plagiobothrys scouleri var. hispidulus	0–29	–
	lemon scurfpea	PSLA3	Psoralidium lanceolatum	0–29	–
	slimflower scurfpea	PSTE5	Psoralidium tenuiflorum	0–29	–
	upright prairie coneflower	RACO3	Ratibida columnifera	0–29	–
	veiny dock	RUVE2	Rumex venosus	0–29	–
	ragwort	SENEC	Senecio	0–29	–
	goldenrod	SOLID	Solidago	0–29	–
	scarlet globemallow	SPCO	Sphaeralcea coccinea	0–29	–
	spiderwort	TRADE	Tradescantia	0–29	–
	American vetch	VIAM	Vicia americana	0–29	–
15	15"-17"			84–252
	Forb, perennial	2FP	Forb, perennial	0–84	–
	Cuman ragweed	AMPS	Ambrosia psilostachya	0–34	–
	pussytoes	ANTEN	Antennaria	0–34	–
	white sagebrush	ARLU	Artemisia ludoviciana	0–34	–
	milkvetch	ASTRA	Astragalus	0–34	–
	false boneset	BREU	Brickellia eupatorioides	0–34	–
	prairie clover	DALEA	Dalea	0–34	–
	larkspur	DELPH	Delphinium	0–34	–
	sanddune wallflower	ERCA14	Erysimum capitatum	0–34	–
	scarlet beeblossom	GACO5	Gaura coccinea	0–34	–
	hairy false goldenaster	HEVI4	Heterotheca villosa	0–34	–
	bush morning-glory	IPLE	Ipomoea leptophylla	0–34	–
	dotted blazing star	LIPU	Liatris punctata	0–34	–
	rush skeletonplant	LYJU	Lygodesmia juncea	0–34	–
	bractless blazingstar	MENU	Mentzelia nuda	0–34	–
	evening primrose	OENOT	Oenothera	0–34	–
	Indian breadroot	PEDIO2	Pediomelum	0–34	–
	beardtongue	PENST	Penstemon	0–34	–
	sleeping popcornflower	PLSCH	Plagiobothrys scouleri var. hispidulus	0–34	–
	lemon scurfpea	PSLA3	Psoralidium lanceolatum	0–34	–
	slimflower scurfpea	PSTE5	Psoralidium tenuiflorum	0–34	–
	upright prairie coneflower	RACO3	Ratibida columnifera	0–34	–
	veiny dock	RUVE2	Rumex venosus	0–34	–
	ragwort	SENEC	Senecio	0–34	–
	goldenrod	SOLID	Solidago	0–34	–
	scarlet globemallow	SPCO	Sphaeralcea coccinea	0–34	–
	white heath aster	SYERE	Symphyotrichum ericoides var. ericoides	0–34	–
	spiderwort	TRADE	Tradescantia	0–34	–
	American vetch	VIAM	Vicia americana	0–34	–
Shrub/Vine
8	12-14"			0–219
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	0–73	–
	silver sagebrush	ARCA13	Artemisia cana	0–29	–
	sand sagebrush	ARFI2	Artemisia filifolia	0–29	–
	prairie sagewort	ARFR4	Artemisia frigida	0–29	–
	fourwing saltbush	ATCA2	Atriplex canescens	0–29	–
	spreading buckwheat	EREF	Eriogonum effusum	0–29	–
	broom snakeweed	GUSA2	Gutierrezia sarothrae	0–29	–
	plains pricklypear	OPPO	Opuntia polyacantha	0–29	–
	western sandcherry	PRPUB	Prunus pumila var. besseyi	0–29	–
	prairie rose	ROAR3	Rosa arkansana	0–29	–
	soapweed yucca	YUGL	Yucca glauca	0–29	–
16	15"-17"			0–252
	Shrub (>.5m)	2SHRUB	Shrub (>.5m)	0–84	–
	silver sagebrush	ARCA13	Artemisia cana	0–34	–
	sand sagebrush	ARFI2	Artemisia filifolia	0–34	–
	prairie sagewort	ARFR4	Artemisia frigida	0–34	–
	fourwing saltbush	ATCA2	Atriplex canescens	0–34	–
	spreading buckwheat	EREF	Eriogonum effusum	0–34	–
	broom snakeweed	GUSA2	Gutierrezia sarothrae	0–34	–
	plains pricklypear	OPPO	Opuntia polyacantha	0–34	–
	western sandcherry	PRPUB	Prunus pumila var. besseyi	0–34	–
	prairie rose	ROAR3	Rosa arkansana	0–34	–
	soapweed yucca	YUGL	Yucca glauca	0–34	–

Interpretations

Animal community

Wildlife Interpretations

Reference Plant Community - Needle and Thread, Prairie Sandreed, Little Bluestem:

The predominance of grasses plus high forb diversity in this community favors large grazers such as pronghorn and elk. Suitable thermal and escape cover for mule deer is limited due to low shrub cover. White-tailed and black- tailed jackrabbit, badger, and coyote commonly use this community. The Reference Plant Community also provides habitat for a wide array of smaller mammals, so diverse prey populations are available for raptors such as ferruginous and Swainson’s hawks. Birds such as Cassin’s and Brewer’s sparrow, chestnut collared longspur, lark bunting, western meadowlark, will utilize this community for nesting and foraging.

1.2 Community - Decreased Prairie Sandreed, Decreased Needle and Thread, Increased Blue Grama:

The reduction in taller grasses in this community results in decreased use by lark buntings and western meadowlarks. Use by long-billed curlew increases, provided there is standing water within one-quarter mile. Killdeer, horned larks, and McCown’s longspurs will also make significant use of this community. Pronghorn may forage in this community.

1.3 Community - Low Plant Density, Increased Litter, Decadent Plants, and Standing Dead Canopy:

This community has low habitat value for most wildlife species. Horned larks may nest in this community.

2.1 Community - Blue Grama, Threadleaf Sedge, Spreading Buckwheat, Broom Snakeweed, and Pricklypear:

As these communities develop into an open landscape the wildlife species will shift from the Reference Plant Community species toward the typical shortgrass prairie species such as horned lark, killdeer, long-billed curlew, McCown's longspur, and ferruginous hawk.

3.1 Community – Threadleaf Sedge, Fendler Threeawn, Annuals, Cheatgrass, and Invasives:

Sparse vegetation and greater amounts of bare ground provide suitable habitat for prairie dogs, horned larks and McCown’s longspurs. However, a lack of complex vegetation structure and residual cover makes this community poor habitat in general for most ground-nesting birds and big game species.

4.1 Community – Threeawn, Sand Dropseed, Annuals, Cheatgrass, and Invasives:

The wildlife species found here will be similar to the Increased Bare Ground Community.

Seeded Community (Adapted Seed Mixes):

Wildlife use of tilled and replanted fields is dependent upon the plant species used in the planted seed mix. Purpose of the seeding (i.e. reclamation, soil erosion control, livestock grazing, targeted wildlife species, etc.) affects the usability for wildlife. If wildlife use is a primary concern, then seed mixes must be formulated to meet species specific habitat requirements.

Grazing Interpretations

The following table is a guide to stocking rates for the plant communities described in the Sandy 12-17 inch PZ site. These are conservative estimates for initial planning. On-site conditions will vary, and stocking rates should be adjusted based on range inventories, animal kind/class, forage availability (adjusted for slope, distance to water), and the type of grazing system (number of pastures, planned moves, etc.), all of which is determined in the conservation planning process.

The following stocking rates are based on the total annual forage production in a normal year multiplied by 25 percent harvest efficiency of preferred and desirable forage species, divided by 912 pounds of ingested air-dry vegetation for an animal unit per month (Natl. Range and Pasture Handbook, 1997). An animal unit month (AUM) is defined as the amount of forage required by one mature cow, for one month.

Plant Community (PC) Production (total lbs./acre in a normal year) and Stocking Rate (AUMs/acre) are listed below:
Example: Reference PC – (1300) (.36)
1,300 lbs. per acre X 25% Harvest Efficiency = 325 lbs. forage demand for one month. Then, 325 lbs. per acre/912 demand per AUM =.36

Plant Community (PC) Production (lbs.ac), and Stocking Rate (AUM/Acre)

12-14 Inch PZ:

1.2 PC - (900) (0.25)
2.1 PC - (500) (0.14)

15-17 Inch PZ
Reference PC – (1500) (0.41)
1.2 PC – (1100) (0.30)
2.1 PC – (600) (0.16)

Grazing by domestic livestock is one of the major income-producing industries in the area. Rangelands in this area provide year-long forage under prescribed grazing for cattle, sheep, horses and other herbivores. During the dormant period, livestock may need supplementation based on reliable forage analysis.

An on-site inventory is required prior to development of a grazing plan.

Hydrological functions

Water is the principal factor limiting forage production on this site. This site is dominated by soils in hydrologic group B, with localized areas in hydrologic group C. Infiltration potential for this site varies from moderately rapid to rapid, depending upon soil hydrologic group and ground cover. Runoff varies from low to moderate. In many cases, areas with greater than 75 percent ground cover have the greatest potential for high infiltration and lower runoff. An example of an exception would be where short-grasses form a strong sod and dominate the site. Areas where ground cover is less than 50 percent have the greatest potential to have reduced infiltration and higher runoff (refer to NRCS Section 4, National Engineering Handbook (USDA–NRCS, 1972–2012) for runoff quantities and hydrologic curves).

Rills and gullies should not typically be present. Water flow patterns should be barely distinguishable if at all present. Pedestals are only slightly present in association with bunchgrasses. Litter typically falls in place, and signs of movement are not common. Chemical and physical crusts are rare to non-existent. Cryptogamic crusts are present, but only cover 1 to 2 percent of the soil surface.

Recreational uses

This site provides hunting, hiking, photography, bird watching, and other opportunities. The wide varieties of plants that bloom from spring until fall have an aesthetic value that appeals to visitors.

Wood products

No appreciable wood products are present on the site.

Other products

Site Development & Testing Plan

The Sandy 12-17 inch PZ site was developed by an earlier version of the Sandy (Sy) 12-17 inch Precipitation Zone ESD (2005, updated 2008). The earlier version of the Sandy 12-17 inch PZ ESD were based on input from the Natural Resources Conservation Service (NRCS, formerly the Soil Conservation Service), and historical information obtained from the Sandy 12-14 Southern Plains (SP) and Sandy 15-17 SP Range Site Descriptions (1988). This ESD meets the Provisional requirements of the National Ecological Site Handbook (NESH). This ESD will continue refinement towards an Approved status according to the NESH.

General Data (MLRA and Revision Notes, Hierarchical Classification, Ecological Site Concept, Physiographic, Climate, and Water Features, and Soils Data):

Updated: All “Required” items complete to Provisional level.

Community Phase Data (Ecological Dynamics, STM, Transition & Recovery Pathways, Reference Plant Community, Species Composition List, Annual Production Table):

Updated: All “Required” items complete to Provisional level.

Annual Production Table is from the “Previously Approved” ESD (2008).

The Annual Production Table and Species Composition List will be reviewed for future updates at Approved level. Note: The lbs./ac in the Total Annual Production may need to be increased. It should be more productive than the "Loamy" ESD.

Each Alternative State/Community

Complete to Provisional level

Supporting Information (Site Interpretations, Assoc. & Similar Sites, Inventory Data References, Agency/State Correlation, References)

Updated: All “Required” items complete to Provisional level.
Wildlife Interpretations: Plant community names updated. Narrative is from “Previously Approved” ESD (2008). Wildlife species will need to be updated at the next Approved level.

Livestock Interpretations: Plant community names and stocking rates updated.

Hydrology, Recreational Uses, Wood Products, and Other Products carried over from previously “Approved” ESD (2008).
Plant Preferences tabled removed. Will be released as a technical guide notice by NE and WY state offices in the future.

Existing NRI or 417 Inventory Data References updated.

Reference Sheet
Rangeland Health Reference Sheet carried over from previously “Approved” ESD (2008).
It will be updated at the next “Approved” level.

“Future work, as described in a project plan, to validate the information in this provisional ecological site description is needed. This will include field activities to collect low and medium intensity sampling, soil correlations, and analysis of that data. Annual field reviews should be done by soil scientists and vegetation specialists. A final field review, peer review, quality control, and quality assurance reviews of the ESD will be needed to produce the final document.” (NI 430_306 ESI and ESD, April, 2015)

Supporting information

Inventory data references

Information presented here has been derived from data collection on private and federal lands using:
• Double Sampling (clipped 2 of 5 plots)*
• Rangeland Health**
• Soil Stability**
• Line Point Intercept : Foliar canopy, basal cover (forb, graminoid, shrub, subshrub, lichen, moss, rock fragments, bare ground, percentage of Litter)***
• Soil pedon descriptions collected on site****
*NRCS 528-Prescribed Grazing Standard job sheets.
*Interpreting Indicators of Rangeland Health, Version 4, 2005
*Monitoring Manual for Grassland, Shrubland and Savanna Ecosystems, Volume II, 2005
*Field Book for Describing and Sampling Soils, Version 3, 2012
• NRI- Natural Resource Inventory data
• SCS-RANGE-417 Production & Composition Record for Native Grazing Lands

Date Source: NRI
Number of Records: 28
Sample Period: 2006-2013
States: NE, WY
Counties: Banner, Morrill, Scotts Bluff (NE):
Goshen, Laramie, Platte (WY)

Date Source: 417s
Number of Records: 17
Sample Period: 1970-1986
States: NE, WY
Counties: Banner, Garden, Morrill, Scotts Bluff, Sioux (NE):
Goshen, Laramie (WY)

Additional reconnaissance data collection using numerous ocular estimates and other inventory data; NRCS clipping data for USDA program support, and field observations from experienced range trained personnel also were used to estimate data.

References

Guyette, R.P., M.C. Stambaugh, D.C. Dey, and R. Muzika. 2012. Predicting Fire Frequency with Chemistry and Climate. Ecosystems 15:322–335.
Stewart, O.C., H.T. Lewis, and M.K. Anderson. 2002. Forgotten Fires: Native Americans and the Transient Wilderness. University of Oklahoma Press, Norman, OK. 351p.

Other references

Anderson, R.C. 2006. Evolution and origin of the central grassland of North America: Climate, fire, and mammalian grazers. Journal of the Torrey Botanical Society 133:626–647.

Bragg, T.B. 1995. The physical environment of the Great Plains grasslands. In: The changing prairie. A. Joern and K.H. Keeler (eds.) Oxford University Press, Oxford, UK. pp. 49–81.

Branson, D.H., and G.A. Sword. 2010. An experimental analysis of grasshopper community responses to fire and livestock grazing in a northern mixed- grass prairie. In: Environmental Entomology 39:1441–1446.

Brinson, M.M. 1993. A hydrogeomorphic classification for wetlands. Technical Report WRP–DE–4. U.S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, MS.

Cleland, D., P. Avers, W.H. McNab, M. Jensen, R. Bailey, T. King, and W. Russell. 1997. National Hierarchical Framework of Ecological Units, published in Ecosystem Management: Applications for Sustainable Forest and Wildlife Resources, Yale University Press

Coupland, R.T. 1958. The effects of fluctuations in weather upon the grasslands of the Great Plains. In: Botanical Review 24:273–317.

Davis, S.K., R.J. Fisher, S.L. Skinner, T.L. Shaffer, and R.M. Brigham. 2013. Songbird abundance in native and planted grassland varies with type and amount of grassland in the surrounding landscape. Journal of Wildlife Management 77:908–919.

DeLuca, T.H., and P. Lesica. 1996. Long-term harmful effects of crested wheatgrass on Great Plains grassland ecosystems. In: Journal of Soil and Water Conservation 51:408–409.

Derner, J.D., and R.H. Hart. 2007. Grazing-induced modifications to peak standing crop in northern mixed-grass prairie. Rangeland Ecology and Management 60:270–276.

Derner, J.D., and A.J. Whitman. 2009. Plant interspaces resulting from contrasting grazing management in northern mixed-grass prairie: Implications for ecosystem function. In: Rangeland Ecology and Management 62:83–88.

Derner, J.D., W.K. Lauenroth, P. Stapp, and D.J. Augustine. 2009. Livestock as ecosystem engineers for grassland bird habitat in the western Great Plains of North America. In: Rangeland Ecology and Management 62:111–118.

Dillehay, T.D. 1974. Late Quaternary bison population changes on the southern Plains. In: Plains Anthropologist 19:180–196.

Dormaar, J.F., and S. Smoliak. 1985. Recovery of vegetative cover and soil organic matter during revegetation of abandoned farmland in a semiarid climate. In: Journal of Range Management 38:487–491.

Fenneman, N.M., and D.W. Johnson. 1946. Physical divisions of the United States. U.S. Geological Survey, Physiographic Committee. Scale 1:700,000.

Harmoney, K.R. 2007. Grazing and burning Japanese brome (Bromus japonicus) on mixed grass rangelands. In: Rangeland Ecology and Management 60:479–486.

Heitschmidt, R.K., and L.T. Vermeire. 2005. An ecological and economic risk avoidance drought management decision support system. In: Pastoral systems in marginal environments, 20th International Grasslands Congress, July 2005. J.A. Milne (ed.) p. 178.

Knopf, F.L. 1996. Prairie legacies—Birds. In: Prairie conservation: Preserving North America’s most endangered ecosystem, Island Press, Washington, DC. F.B. Samson and F.L. Knopf (eds.) pp. 135–148.

Knopf, F.L., and F.B. Samson. 1997. Conservation of grassland vertebrates. In: F.B. Samson and F.L. Knopf (eds) Ecology and conservation of Great Plains vertebrates: Ecological Studies 125, Springer-Verlag, New York, NY. pp. 273–289.

Lauenroth, W.K., O.E. Sala, D.P. Coffin, and T.B. Kirchner. 1994. The importance of soil water in recruitment of Bouteloua gracilis in the shortgrass steppe. In: Ecological Applications 4:741–749.

Laycock, W.A. 1988. History of grassland plowing and grass planting on the Great Plains. In: Impacts of the Conservation Reserve Program in the Great Plains—symposium proceedings, September 16–18, 1987. J.E. Mitchell (ed.) USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, General Technical Report RM-158.

Malloch, D.W., K.A. Pirozynski, and P.H. Raven. 1980. Ecological and evolutionary significance of mycorrhizal symbioses in vascular plants (a review). In: Proceedings of the National Academy of Sciences 77:2113–2118.

Ogle, S.M., W.A. Reiners, and K.G. Gerow. 2003. Impacts of exotic annual brome grasses (Bromus spp.) on ecosystem properties of the northern mixed grass prairie. In: American Midland Naturalist 149:46–58.

Roath, L.R. 1988. Implications of land conversions and management for the future. In: J.E. Mitchell (ed.) Impacts of the Conservation Reserve Program in the Great Plains—symposium proceedings, September 16–18, 1987. USDA Forest Service, Rocky Mountain Forest and Range Experiment Station, General Technical Report RM-158.

Smoliak, S., and J.F. Dormaar. 1985. Productivity of Russian wildrye and crested wheatgrass and their effect on prairie soils. On: Journal of Range Management 38:403–405.

Smoliak, S., J.F. Dormaar, and A. Johnston. 1972. Long-term grazing effects on Stipa-Bouteloua prairie soils. In: Journal of Range Management 25:246–250.

Soil Science Division Staff. 2017. Soil survey manual. USDA Handbook 18. Government Printing Office, Washington, DC.

Soil Survey Staff. Official Soil Series Descriptions. USDA Natural Resources Conservation Service. Available online. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/home/?cid=nrcs142p2_053587. Accessed 15 November, 2017.

Soil Survey Staff. Soil Survey Geographic (SSURGO) database. USDA Natural Resources Conservation Service.

Soil Survey Staff. 2014. Keys to Soil Taxonomy, 12th edition. USDA Natural Resources Conservation Service, Washington, DC.

Soil Survey Staff. 2018. Web Soil Survey. USDA Natural Resources Conservation Service. Available online. https://websoilsurvey.nrcs.usda.gov/app/ Accessed 15 February, 2018.

Soller, D.R. 2001. Map showing the thickness and character of Quaternary sediments in the glaciated United States east of the Rocky Mountains. In: U.S. Geological Survey Miscellaneous Investigations Series I-1970-E, scale 1:3,500,000.

U.S. Army Corps of Engineers. 1987. Corps of Engineers wetlands delineation manual. Wetlands Research Program Technical Report Y-87-1 Available online. http://www.lrh.usace.army.mil/Portals/38/docs/USACE%2087%20Wetland%20Delineation%20Manual.pdf. Accessed November 11, 2017. Waterways Experiment Station, Vicksburg, MS.

U.S. Department of Agriculture, Natural Resources Conservation Service. Glossary of landform and geologic terms. National Soil Survey Handbook, Title 430-VI, Part 629.02c. Available online. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054242. Accessed 16 January,2018.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2010a. Field indicators of hydric soils in the United States, version 7.0.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2013a. Climate data. National Water and Climate Center. Available online. http://www.wcc.nrcs.usda.gov/climate. Accessed October 13, 2017.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2006. Land resource regions and major land resource areas of the United States, the Caribbean, and the Pacific Basin. Agriculture Handbook 296.

U.S. Department of Agriculture, Natural Resources Conservation Service. 2013b. National Soil Information System. Available online. https://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/survey/geo/?Cid=nrcs142p2_053552. Accessed 30 October, 2017.

U.S. Department of the Interior, Geological Survey. 2008. LANDFIRE 1.1.0 Vegetation Dynamics Models. Available online. http://landfire.cr.usgs.gov/viewer/. Accessed October 30, 2017.

U.S. Department of the Interior, Geological Survey. 2011. LANDFIRE 1.1.0 Existing Vegetation Types. http://landfire.cr.usgs.gov/viewer/.
Willeke, G.E. 1994. The national drought atlas [CD ROM]. U.S. Army Corps of Engineers, Water Resources Support Center, Institute for Water Resources Report 94-NDS-4.

Wilson, S.D., and J.M. Shay. 1990. Competition, fire, and nutrients in a mixed-grass prairie. In: Ecology 71:1959–1967.

With, K.A. 2010. McCown’s longspur (Rhynchophanes mccownii). In: A. Poole (ed.) The birds of North America, Cornell Lab of Ornithology, Ithaca, NY. Available online. https://birdsna.org/Species-Account/bna/home.Accessed October 13, 2017.

Additional References:

Augustine, D.J., J. Derner, D. Milchunas, D. Blumenthal, and L. Porensky. 2017. Grazing moderates increases in C3 grass abundance over seven decades across a soil texture gradient in shortgrass steppe. In: Journal of Vegetation Science, Doi:10.1111/jvs.12508, International Association of Vegetative Science

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 1997, revised 2003.
National Range and Pasture Handbook. Available online. http://www.glti.nrcs.usda.gov/technical/publications/nrph.html. Accessed 26 February, 2018.

Clark, J., E. Grimm, J. Donovan, S. Fritz, D. Engrstom, and J. Almendinger. 2002. Drought cycles and landscape responses to past aridity on prairies of the Northern Great Plains, USA. In: Ecology, 83(3), 595-601.

Collins, S., and S. Barber. (1985). Effects of disturbance on diversity in mixed-grass prairie. In: Vegetatio, 64, 87-94.

Cooperative climatological data summaries. NOAA. Western Regional Climate Center: Reno, NV. Web. Available online. http://www.wrcc.dri.edu/climatedata/climsum. Accessed November 16, 2017).

Egan, Timothy. 2006. The Worst hard time. Houghton Mifflin Harcourt Publishing Company: New York, NY.

Guyette, Richard P., M.C. Stambaugh, D.C. Dey, RM Muzika. 2012. Predicting fire frequency with chemistry and climate. In: Ecosystems, 15: 322-335

Hart, R. and J. Hart. 1997. Rangelands of the Great Plains before European Settlement. In: Rangelands, 19(1), 4-11.

Hart, R. 2001. Plant biodiversity on shortgrass steppe after 55 years of zero, light, moderate, or heavy cattle grazing. In: Plant Ecology, 155, 111-118.

Pellant, M., P. Shaver, D.A. Pyke, J.E. Herrick. 2005. Interpreting indicators of rangeland health, Version 4. BLM National Business Center Printed Materials Distribution Service: Denver, CO.

Mack, Richard N. and J.N. Thompson. 1982. Evolution in Steppe with Few Large, Hooved Mammals. In: The American Naturalist. 119, No. 6, 757-773

Reyes-Fox, M., Stelzer H., Trlica M.J., McMaster, G.S., Andales, A.A., LeCain, D.R., and Morgan J.A. 2014. Elevated CO2 further lengthens growing season under warming conditions. In: Nature, April 23, 2014. Available online. http://www.nature.com/nature/journal/v510/n7504/full/nature13207.html. Accessed March 1, 2017.

Schoeneberger, P.J., D.A. Wysockie, E.C. Benham, and Soil Survey Staff. 2012. Field book for describing and sampling soils, Version 3.0. Natural Resources Conservation Service, National Soil Survey Center: Lincoln, NE.

Stahl, David W., E.R. Cook, M.K. Cleaveland, M.D. Therrell, D.M. Meko, H.D. Grissino-Mayer, E. Watson, and B.H. Luckman. Tree-ring data document 16th century megadrought over North America. 2000. In: Eos, 81(12), 121-125.

Stubbendieck, James, S.L. Hatch, L.M. Landholt., 2003. North American wildland plants. Univ. of Nebraska Press, Lincoln and London.

Zelikova, Tamara Jane, D.M. Blumenthal, D.G. Williams, L. Souza, D.R. LeCain, J.Morgan. 2014. Long-term exposure to elevated CO2 enhances plant community stability by suppressing dominant plant species in a mixed-grass prairie. In: Ecology, 2014. Available online. www.pnas.org/cgi/doi/10.1073/pnas.1414659111

U.S. Department of Agriculture, Natural Resources Conservation Service. National Ecological Site Handbook, Title 190, Part 630, 1st Edition. Available online. https://directives.sc.egov.usda.gov/. Accessed September 15, 2017.

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 2009. Part 630, Hydrology, National Engineering Handbook

U.S. Dept. of Agriculture, Natural Resources Conservation Service. 1972-2012. National Engineering Handbook Hydrology Chapters. Available online. http://www.nrcs.usda.gov/wps/portal/nrcs/detailfull/national/water/?&cid=stelprdb1043063 . Accessed August 1, 2015.

U.S. Dept. of Agriculture, Natural Resources Conservation Service. National Soil Survey Handbook title 430-VI. Available online. http://www.nrcs.usda.gov/wps/portal/nrcs/detail/soils/ref/?cid=nrcs142p2_054242

U.S. Dept. of Agriculture, Natural Resources Conservation Service. Web Soil Survey. http://websoilsurvey.sc.egov.usda.gov/App/WebSoilSurvey.aspx. Accessed November 15, 2017.

Data collection for this ecological site was done in conjunction with the progressive soil surveys within the 67A Central High Plains (Northern Part) of Nebraska, Wyoming, and Colorado. It has been mapped and correlated with soils in the following soil surveys:

U.S. Dept. of Agriculture.1994. Soil Survey of Banner County, Nebraska.

U.S. Dept. of Agriculture. 1997. Soil Survey of Cheyenne County, Nebraska.

U.S. Dept. of Agriculture. 1999. Soil Survey of Garden County, Nebraska.

U.S. Dept. of Agriculture. 2005. Soil Survey of Kimball County, Nebraska.

U.S. Dept. of Agriculture. 1985. Soil Survey of Morrill County, Nebraska.

U.S. Dept. of Agriculture. 1968 Soil Survey of Scotts Bluff County, Nebraska.

U.S. Dept. of Agriculture.2013. Soil Survey of Scotts Bluff National Monument, Nebraska

Non-discrimination statement
In accordance with Federal civil rights law and U.S. Department of Agriculture (USDA) civil rights regulations and policies, the USDA, its Agencies, offices, and employees, and institutions participating in or administering USDA programs are prohibited from discriminating based on race, color, national origin, religion, sex, gender identity (including gender expression), sexual orientation, disability, age, marital status, family/parental status, income derived from a public assistance program, political beliefs, or reprisal or retaliation for prior civil rights activity, in any program or activity conducted or funded by USDA (not all bases apply to all programs). Remedies and complaint filing deadlines vary by program or incident.

Persons with disabilities who require alternative means of communication for program information (e.g., Braille, large print, audiotape, American Sign Language, etc.) should contact the responsible Agency or USDA's TARGET Center at (202) 720-2600 (voice and TTY) or contact USDA through the Federal Relay Service at (800) 877-8339. Additionally, program information may be made available in languages other than English.
To file a program discrimination complaint, complete the USDA Program Discrimination Complaint Form, AD-3027, found online at How to File a Program Discrimination Complaint and at any USDA office or write a letter addressed to USDA and provide in the letter all of the information requested in the form. To request a copy of the complaint form, call (866) 632-9992. Submit your completed form or letter to USDA by: (1) mail: U.S. Department of Agriculture, Office of the Assistant Secretary for Civil Rights, 1400 Independence Avenue, SW, Washington, D.C. 20250-9410; (2) fax: (202) 690-7442; or 3) email: program.intake@usda.gov.

Contributors

Kimberly Diller, Ecological Site Specialist, NRCS MLRA SSO, Pueblo CO
Andy Steinert, MLRA 67B Soil Survey Leader, NRCS MLRA SSO, Fort Morgan, CO
Doug Whisenhunt, Ecological Site Specialist, NRCS MLRA SSO, Pueblo CO

Approval

Kirt Walstad, 9/07/2023

Acknowledgments

Partners/Contributors:
David Cook, Rangeland Management Specialist, NRCS, Oshkosh, NE
George Gamblin, Rangeland Management Specialist, NRCS, Wheatland, WY
Cameron Clark, Resource Soil Scientist, NRCS, Douglas, WY
Angie Elg, Resource Soil Scientist, NRCS, Scottsbluff, NE
Tim Becket, Area Resource Conservationist, Douglas, WY
Mitchell Stephenson, Ph.D. Rangeland Management Specialist, UNL-Panhandle Research Station, Scottsbluff, NE
Kristin Dickinson, District Conservationist, NRCS, Sidney, NE
Rick Peterson, Ecological Site Inventory Specialist, SD-NRCS-MLRA SSO, Rapid City, SD

Program Support:
Nadine Bishop, NE State Rangeland Management Specialist/ QC, NRCS, Imperial, NE
John Hartung, WY State Rangeland Management Specialist/ QC, NRCS, Casper, WY
David Kraft, NRCS MLRA Ecological Site Specialist-QA, Emporia, KS
James Bauchert, WY State Soil Scientist, WY-NRCS, Casper, WY
Neil Dominy, NE State Soil Scientist, NRCS, Lincoln, NE
Britt Weiser, NE State Resource Conservationist, NRCS, Lincoln, NE
Clayton Schmitz, WY State Resource Conservationist, NRCS, Casper, WY
Carla Green Adams, Editor, NRCS-SSR5, Denver, CO
Chad Remley, Regional Director, N. Great Plains Soil Survey, Salina, KS
Those involved in developing the 2008 version: Chuck Ring, Rangeland Management Specialist, WY-NRCS; Everett Bainter, WY State Rangeland Management Specialist, WY-NRCS

Rangeland health reference sheet

Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.

Author(s)/participant(s)	Dave Cook, Kristin Dickinson, George Gamblin, John Hartung, Andy Steinert, Nadine Bishop
Contact for lead author
Date	11/03/2020
Approved by	Kirt Walstad
Approval date
Composition (Indicators 10 and 12) based on	Annual Production

Indicators

Number and extent of rills:
None. Rills are not expected on the site.
Presence of water flow patterns:
Typically, none. Water flow patterns, if present, are associated with animal activity on slopes greater than 6 percent and will be very short, narrow, and disconnected.
Number and height of erosional pedestals or terracettes:
Typically, None.
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
Bare ground is typically is 5 to 10 percent and scattered in patches less than 3 inches (7.62 cm) wide.
Number of gullies and erosion associated with gullies:
None. Gullies should not be present on this site.
Extent of wind scoured, blowouts and/or depositional areas:
None, wind-scoured areas and depositional areas are not expected on this site.
Amount of litter movement (describe size and distance expected to travel):
Litter should fall in place. Slight amount of movement of fine litter from water is possible, but not normal. Litter movement from wind is not expected.
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
Soil aggregate stability ratings should typically be 5 to 6, normally 6. Surface organic matter adheres to the soil surface. Soil surface peds will typically retain structure indefinitely when dipped in distilled water.

Surface erosion by water rarely occurs due to rapid infiltration, but surface is susceptible to wind erosion when vegetative cover is reduced due to multi-year drought, wildfire, or multi-year heavy grazing.

Biological crusts may be present (up to 10 percent of the surface) and serve to provide resistance to erosion.
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
Surface layer should be 5 to 12 inches (12.7-30.5 cm) thick. Soil colors vary with soil series from dark grayish brown, grayish brown, to brown (values of 4 to 5) when dry and dark grayish or very dark grayish brown (values of 3 to 4) when moist. Vonalee and Keeline soils are yellowish brown (5/4) dry and brown (4/3) moist. Structure typically is fine to medium granular.
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
The functional/structural groups provide a combination of rooting depths and structure which positively influences infiltration. Combination of shallow and deep rooted species (mid & tall rhizomatous and tufted perennial cool season grasses) with fine and coarse roots positively influences infiltration. The expected composition of the plant community is 70 to 95 percent perennial grasses and grass-likes, 5 to 15 percent forbs, and 0 to 15 percent shrubs.

In the 12-14” PZ, the perennial grass and grass-like component is made up of tall, warm-season, rhizomatous grasses (10-35%); cool-season bunch grasses (15-40%); mid, warm season grasses (5-25%), short, warm-season grasses (5-15%); cool-season rhizomatous grasses (5-10%); and grass-likes (0-10%).

In the 15-17” PZ, the perennial grass and grass-like component is made up of tall, warm-season, rhizomatous grasses (15-40%); cool-season bunch grasses (10-40%); mid, warm season grasses (5-25%), short, warm-season grasses (5-15%); cool-season rhizomatous grasses (5-10%); and grass-likes (0-10%).
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
None. A compaction layer should not be present.
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):

Dominant:
12-14” PZ: Community 1.1:
1. Native, C3, bunch grasses– 195-520 #/ac (15-40%), 1 species minimum
2. Native, C4, tall, rhizomatous grasses – 130-455 #/ac (10-35%), 1 species minimum

15-17” PZ: Community 1.1:
1. Native, C3, bunch grasses– 225-600 #/ac (15-40%), 1 species minimum
2. Native, C4, tall, rhizomatous grasses – 150-600 #/ac (10-40%), 1 species minimum

Sub-dominant:
12-14” PZ: Community 1.1:
3. Native, C4, mid-grasses – 65-325 #/ac (5-25%), 1 species minimum
4. Native, C4, short grasses – 65-195 #/ac (5-15%), 1 species minimum
5. Shrubs, cacti, vines – 13-195#/ac (1-15%), 1 species minimum
6. Native, Perennial and Annual Forbs – 65-195 #/ac (5-15%), 5 species minimum

15-17” PZ: Community 1.1:
3. Native, C4, mid-grasses – 75-375 #/ac (5-15%), 1 species minimum
4. Native, C4, short grasses – 75-225 #/ac (5-15%), 1 species minimum
5. Shrubs, cacti, vines – 15-225 #/ac (1-15%), 1 species minimum
6. Native, Perennial and Annual Forbs – 75-225 #/ac (5-15%), 5 species minimum

Other:
Minor:
12-14” PZ: Community 1.1:
7. Native, C3, rhizomatous grasses – 65-130 #/ac (5-10%)
8. Grass-likes – 0-130 #/ac: (0-10%)

15-17” PZ: Community 1.1:
7. Native, C3, rhizomatous grasses – 75-150 #/ac (5-10%)
8. Grass-likes – 0-150 #/ac: (0-10%)

Additional:
12-14” PZ: Community 1.1:
12a. Relative Dominance:
Native, C3, bunch grasses = Native, C4, tall and mid grasses > Native, C4, Mid-grasses > C4, short grasses = Native, Perennial and Annual Forbs > or = Shrubs, cacti, vine > Native, C3, Rhizomatous Grasses > Grass-likes

12b. F/S Groups not expected for the site: Introduced annual grasses, perennial introduced and naturalized grasses, trees.

12c. Number of F/S Groups: 8

12d. Species number in Dominant and Sub-dominant F/S Groups: 10

15-17” PZ: Community 1.1:
12a. Relative Dominance:
Native, C3, bunch grasses = Native, C4, tall grasses > Native, C4, Mid-grasses = C4, short grasses = Native, Perennial and Annual Forbs > or = Shrubs, cacti, vine > Native, C3, Rhizomatous Grasses > Grass-likes

12b. F/S Groups not expected for the site: Introduced annual grasses, perennial introduced and naturalized grasses, trees.

12c. Number of F/S Groups: 8

12d. Species number in Dominant and Sub-dominant F/S Groups: 10
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
Very little evidence of decadence or mortality. Bunch grasses have strong, healthy centers with less than 3 percent mortality and shrubs have few dead stems. The exception is the potential of up to 10 percent mortality in the 15-17” PZ and up to 15 percent mortality in the 12-14” PZ of mid and short, warm-season bunch grasses during multi-year drought cycles.
Average percent litter cover (%) and depth ( in):
Plant litter cover is evenly distributed throughout the site and is expected to be 50 to 70 percent. Litter depth is expected to be 0.25-0.50 inch (0.65-1.3 cm). Litter cover during and following drought can range from 40 to 50 percent and 5 to 15 percent following wildfire.
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
In the 12-14” precipitation zone, annual production ranges from 750 to 1750 pounds per acres (air dry basis) Average annual production is 1,300 pounds per acre under normal precipitation and weather conditions.

In the15-17” Precipitation Zone, annual production ranges from 1000 to 2000 pounds per acre (air dry basis). Average annual production is 1,500 pounds per acre under normal precipitation and weather conditions.

No significant reduction is expected in the growing season following wildfire.
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
Annual bromes, common mullein, crested wheatgrass, fringed sagewort, hairy gold aster, and others as they become known.

See:
Colorado Department of Agriculture Invasive Species Website: https://www.colorado.gov/pacific/agconservation/noxious-weed-species
Wyoming Weed and Pest Council Website: https://wyoweed.org/
Nebraska Invasive Species website: https://neinvasives.com/plants
Perennial plant reproductive capability:
All perennial species exhibit high vigor relative to recent weather conditions. Perennial grasses should have vigorous rhizomes or tillers; vegetative and reproductive structures are not stunted. All perennial species should be capable of reproducing annually.